This invention relates to an improved apparatus for introducing gas under pressure into a pipe, such as a pipe which is part of a pipeline adapted for conveying granular particles. One example of a use for such an apparatus is in the conversion of coal to coke. In this example, gas jet plug assemblies of this invention are used for the introduction of super-heated steam under pressure into a pipeline charging system which carries coal particles to a coke oven.
Prior art apparatus for introducing steam into a pipeline are disclosed in the following United States Patents. U.S. Pat. Nos. 3,457,141 and 3,523,065 to Schmidt disclose a jet plug 52 which is illustrated most clearly in FIG. 5 of each patent. U.S. Pat. Nos. 3,432,398 and 3,537,755 to Schmidt disclose a jet nozzle 37 which is illustrated most clearly in FIGS. 2 and 3 of each patent. U.S. Pat. No. 3,374,151 to Schmidt discloses a plug 135 which is illustrated most clearly in FIGS. 4 and 5.
The prior art apparatus disclosed in the foregoing patents consists of one element, a plug. This prior art plug is attached directly to a wall of a pipe by means of exterior threads on the downstream end of the plug. A steam supply line is fitted into the upstream end of the plug by means of interior threads in the plug.
Another prior art apparatus, not disclosed in the foregoing patents, consists of two elements; a plug and a sleeve. This second prior art plug is supported by the prior art sleeve. The prior art sleeve is adapted to be attached to a wall of a pipe, such as by means of welds. The prior art sleeve has an interior bore and interior screw threads. The second prior art plug has exterior screw threads and is adapted to fit into the bore of the sleeve. The exterior screw threads of the second prior art plug engage the interior screw threads of the prior art sleeve. The steam line is fitted into the upstream end of the plug.
It is desirable to improve the design of the prior art gas jet plug assemblies in the following ways. First, it is desirable to have a design which would better facilitate positioning the plug so that the surface on the downstream end of the plug, which is positioned in the interior of the pipe, is precisely aligned with the adjacent interior surface of the pipe, without the plug either extending too far into the pipe or not far enough. Second, it is desirable to have a design which would better facilitate positioning nozzles at the downstream end of the plug to be pointed in precisely the correct direction with reference to the direction of flow of coal particles within the pipe. Third, it would simplify manufacturing of the plug if an interior bore in the plug leading to the nozzles was substantially parallel to the longitudinal axis of the plug.